Abstract
Skeletal mesio-occlusion is one of the most common malocclusions in Japanese children. Incidence of the impaction of the upper central incisor is also relatively high. It is, however, considered to be rather rare in an individual who exhibits congenital missing of the first permanent molars and discrepancies along with these anomalies. Dental care for the developing occlusion of a Japanese girl having all of the above-mentioned anomalies was performed from 8 year-0 month of age upto the fully mature stage of the occlusion.
The chin cap therapy with orthopedic force was used for treatment of the skeletal mesio-occlusion, from 8 year-2 month to 15 year-2 month of age. Unerupted bilateral upper first molars and an impacted upper right central incisor were found at the time of first visit. The unerupted upper molars were diagnosed as the second molars due to the developmental level and the coronal morphology, while the upper first molars were accordingly diagnosed as agenesis. The upper right and left second molars erupted in the position of first molars at 9 year-11 month and 9 year-7 month of age respectively. Discrepancies in the dentitions were respectively solved by excision of the impacted upper right central incisor and by extraction of the lower left central incisor. A multi-brackets appliance was used along with the chin cap therapy for the final alignment correction The upper right lateral incisor aligned at the position of the excised upper right central incisor was restored with the jacket crown having the crown contour of the upper right central incisor. In this case, a functionally as well as an esthetically satisfied permanent occlusion was obtained.
